Had the same noise when i first got my focus 1.8 diesel 02 plate, disappeared after a couple of months of having the car when i got an oil change carried out. 2 years later i got Kwik Fit to do another oil change and the noise started again, so got the original garage to get the oil changed again after 3 weeks of kwik fit doing it, and had another oil filter change but the noise is still there to this day. Only does it once the car is warmed up, usually at an average of 2000 revs. Has everyone got the same model car i have that this happens to?

Wish I knew what causes the noise as I fear taking my car back into garage for another oil change, and the noise returning. Maybe a while though as my Mechanic told me I can do 15,000 miles on an oil change these days as it's synthetic.

On a slightly different note and this could be an impossible question, but how much do we think I expect to get out of this great engine. Currently on 189,000 and keeping fingers crossed I get to ideally at least 220,000